sedimentary

Fossiliferous Limestone

Carbonate Sedimentary Rock (primarily CaCO3)

AI-generated identification · may be incorrect

Hardness: 3-4 (Mohs scale); Color: Cream, tan, or gray; Luster: Dull/earthy; Structure: Clastic or crystalline with visible fossil fragments; Cleavage: None/clastic texture.

Hardness: 3-4 (Mohs scale)
Color: Cream, tan, or gray
Luster: Dull/earthy

Identified July 18, 2026More sedimentary →

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Physical properties

Hardness: 3-4 (Mohs scale); Color: Cream, tan, or gray; Luster: Dull/earthy; Structure: Clastic or crystalline with visible fossil fragments; Cleavage: None/clastic texture.

Formation & geological history

Formed over millions of years by the accumulation and lithification of organic debris like shells, coral, and algae in warm, shallow marine environments. Common in marine paleo-basin systems.

Uses & applications

Used extensively in the construction industry as building stone, road base, and raw material for cement (Portland cement) and lime production.

Geological facts

Limestone makes up about 10% of the total volume of all sedimentary rocks. It often contains significant marine fossils and is the primary rock found in karst landscapes (caves and sinkholes).

Field identification & locations

Identified in the field by its light color, presence of visible shell fragments or fossils, and its reaction (effervescence/bubbling) when a drop of diluted hydrochloric acid is applied.